M. Miller on the Development. of Chara. 261 
observed in Chara, because the cells become opake too soon and 
rarely permit of their contents being distinguished, as they are 
rapidly deposited on the walls of their cells. One circumstance 
however remains inexplicable, which is, that in one cell (fig. 9) 
there are cytoblasts which appear as if they were divided into 
two parts; one in the third upper cell still with its apex in the 
third, the greater part being in the upper one (had the cytoblast, 
which was formed in the third. cell, really ruptured this to form 
a new cell?); and lastly, that the cytoblast of the uppermost 
cell, as also the cell itself, appeared as if contracted exactly at the 
centre ! 
The membrane of the new cells, which is formed in an an- 
nular manner by the cytoblasts (this is also Schleiden’s view), 
is Mohl’s primordial utricle*. It can hardly be seen more beau- 
tifully in situ in other parts than in the lowermost joint of the 
stem of the germinating plant (figs. 7 and 8). It is here a simple 
induration of that external lamina of the cytoblasts which les im- 
mediately on the internal periphery of the stem membrane. The 
membrane which surrounds the cytoblast is perfectly analogous 
to that produced by induration. Both are coloured yellowish or 
brownish by iodine. Hence Mohl is correct, when he sayst, “ The 
substance of which the primordial utricle consists, appears, if not 
identical with, at least nearly related to the mucous granular sub- 
stance which usually envelopes the nucleus in the form of an ir- 
regular mass, and from which the mucous threads which are so 
frequently met with im the young cells emanate, since these dif- 
ferent portions react in the same manner with iodine and sulphuric 
acid.” We ought to consider them, as stated above, to be iden- 
tical. The same author’s opinion also ft, that the primordial 
utricle might be of a nitrogenous nature, considering the above 
reaction of iodine and sulphuric acid, the latter of which does not 
cause it to disappear, regarded by French chemists as a proof of 
its containing nitrogen, appears susceptible of direct proof from 
the above facts. . For if the formation of the cytoblastema from 
starch and that of the cytoblasts and primordial ‘utricle from the 
former can be directly observed, the conclusion regarding nitro- 
gen is not too bold, if we remember the large amount of nitrogen 
contained in the gluten of starch. And starch is always found 
naturally combined with this substance ! 
When the primordial utricle is once perfectly formed, it ap- 
pears as a transparent, completely closed peripheral membrane, 
which is entirely separated by iodine from the outer cell-mem- 
brane and envelopes the cell-contents. It adheres to it in the 
upper cells equally as strongly as we previously found it do in 
* Grundzug, 2te Ausg. + Bot. Zeit. 1844, p. 244. t L. e. p. 305. 
